不同桩-土界面直剪试验研究

为探讨桩-土界面的摩擦特性，进行了混凝土-土、钢板-土、HDPE-土3组桩-土界面室内的直剪试验，每组试验均施加6个法向应力。结果表明:不同桩-土界面的剪切强度均随垂直压力的增大而增大；在同一法向应力下，三种不同界面的剪应力-位移曲线的初始阶段变化不大，但曲线的后半段随法向应力的增大有明显变化；法向应力较小时，各界面的剪应力变化不大；法向应力较大时，表现出HDPE-土界面的剪切强度最大。

Experimental Study on Direct Shear of Different Pile-Soil Interface

In order to explore the frictional behavior of pile-soil interface,the direct shear of three pile-soil interfaces,i.e.concrete-soil,steel plate-soil,HDPE-soil are separately tested indoor,in which,6 normal stresses are applied.The results show that shear strength of pile-soil interfaces increases with vertical pressure increased;under the same normal stress,shear strength-displacement curve of each interface does not change much in the initial section,but it changes significantly in the latter section with the increase of stress;when normal stress is small,shear strength of each interface does not change much;when normal stress is larger,HDPE-soil interface has the maximum shear strength.